﻿using System;
using System.IO;
using System.Web;
using System.Drawing;
using System.Drawing.Imaging;
using AspDIY.Net.Drawing.Gif;

namespace AspDIY.Net.Common
{
    /// <summary>
    ///  验证码类
    /// </summary>
    public partial class VerifyCode : System.Web.UI.Page
    {
        #region 成员

        #region 是否动态验证码
        bool isgif = false;
        /// <summary>
        ///  是否动态验证码(默认否)
        /// </summary>
        public bool IsGif
        {
            get { return isgif; }
            set { isgif = value; }
        }
        #endregion

        #region 验证码长度(默认6个验证码的长度)
        int length = 6;
        /// <summary>
        ///  验证码长度(默认6个验证码的长度)
        /// </summary>
        public int Length
        {
            get { return length; }
            set { length = value; }
        }
        #endregion

        #region 验证码字体大小(为了显示扭曲效果，默认40像素，可以自行修改)
        int fontSize = 12;
        /// <summary>
        ///  验证码字体大小(为了显示扭曲效果，默认40像素，可以自行修改)
        /// </summary>
        public int FontSize
        {
            get { return fontSize; }
            set { fontSize = value; }
        }
        #endregion

        #region 边框补(默认1像素)
        int padding = 2;
        /// <summary>
        ///  边框补(默认2像素)
        /// </summary>
        public int Padding
        {
            get { return padding; }
            set { padding = value; }
        }
        #endregion

        #region 是否输出燥点(默认输出)
        bool chaos = true;
        /// <summary>
        ///  是否输出燥点(默认不输出)
        /// </summary>
        public bool Chaos
        {
            get { return chaos; }
            set { chaos = value; }
        }
        #endregion

        #region 是否输出干扰线
        bool ispoint = true;
        /// <summary>
        /// 是否输出干扰线(默认是)
        /// </summary>
        public bool IsPoint
        {
            get { return ispoint; }
            set { ispoint = value; }
        }
        #endregion

        #region 干扰线条数
        int pointnum = 10;
        /// <summary>
        /// 干扰线条数(默认10条)
        /// </summary>
        public int PointNum
        {
            get { return pointnum; }
            set { pointnum = value; }
        }
        #endregion

        #region 自定义背景色(默认白色)
        Color backgroundColor = Color.White;
        /// <summary>
        /// 自定义背景色(默认白色)
        /// </summary>
        public Color BackgroundColor
        {
            get { return backgroundColor; }
            set { backgroundColor = value; }
        }
        #endregion

        #region 是否开启波形滤镜
        bool istwist = true;
        /// <summary>
        ///  是否动态验证码(默认否)
        /// </summary>
        public bool IsTwist
        {
            get { return istwist; }
            set { istwist = value; }
        }
        #endregion

        #region 自定义随机颜色数组
        Color[] colors = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };
        /// <summary>
        /// 自定义随机颜色数组
        /// </summary>
        public Color[] Colors
        {
            get { return colors; }
            set { colors = value; }
        }
        #endregion

        #region 自定义字体数组
        string[] fonts = { "Arial", "Georgia" };
        /// <summary>
        /// 自定义字体数组
        /// </summary>
        public string[] Fonts
        {
            get { return fonts; }
            set { fonts = value; }
        }
        #endregion

        #region 自定义随机码字符串序列(使用逗号分隔)
        string codeSerial = "0,1,2,3,4,5,6,7,8,9,a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z";
        /// <summary>
        /// 自定义随机码字符串序列(使用逗号分隔)
        /// </summary>
        public string CodeSerial
        {
            get { return codeSerial; }
            set { codeSerial = value; }
        }
        #endregion
        #endregion

        #region 产生波形滤镜效果

        private const double PI = 3.1415926535897932384626433832795;
        private const double PI2 = 6.283185307179586476925286766559;

        /// <summary>
        /// 正弦曲线Wave扭曲图片
        /// </summary>
        /// <param name="srcBmp">图片路径</param>
        /// <param name="bXDir">如果扭曲则选择为True</param>
        /// <param name="dMultValue">波形的幅度倍数，越大扭曲的程度越高，一般为3</param>
        /// <param name="dPhase">波形的起始相位，取值区间[0-2*PI)</param>
        /// <returns></returns>
        private System.Drawing.Bitmap TwistImage(Bitmap srcBmp, bool bXDir, double dMultValue, double dPhase)
        {
            System.Drawing.Bitmap destBmp = new Bitmap(srcBmp.Width, srcBmp.Height);

            // 将位图背景填充为白色
            System.Drawing.Graphics graph = System.Drawing.Graphics.FromImage(destBmp);
            graph.FillRectangle(new SolidBrush(System.Drawing.Color.White), 0, 0, destBmp.Width, destBmp.Height);
            graph.Dispose();

            double dBaseAxisLen = bXDir ? (double)destBmp.Height : (double)destBmp.Width;

            for (int i = 0; i < destBmp.Width; i++)
            {
                for (int j = 0; j < destBmp.Height; j++)
                {
                    double dx = 0;
                    dx = bXDir ? (PI2 * (double)j) / dBaseAxisLen : (PI2 * (double)i) / dBaseAxisLen;
                    dx += dPhase;
                    double dy = Math.Sin(dx);

                    // 取得当前点的颜色
                    int nOldX = 0, nOldY = 0;
                    nOldX = bXDir ? i + (int)(dy * dMultValue) : i;
                    nOldY = bXDir ? j : j + (int)(dy * dMultValue);

                    System.Drawing.Color color = srcBmp.GetPixel(i, j);
                    if (nOldX >= 0 && nOldX < destBmp.Width
                     && nOldY >= 0 && nOldY < destBmp.Height)
                    {
                        destBmp.SetPixel(nOldX, nOldY, color);
                    }
                }
            }

            return destBmp;
        }



        #endregion

        #region 生成校验码图片
        /// <summary>
        /// 生成校验码图片
        /// </summary>
        /// <param name="code">字符串</param>
        /// <returns></returns>
        private Bitmap CreateImageBmp(string code)
        {
            int fSize = FontSize;
            int fWidth = fSize + Padding;

            int imageWidth = (int)(code.Length * fWidth) + 4 + Padding * 2;
            int imageHeight = fSize * 2 + Padding;

            System.Drawing.Bitmap image = new System.Drawing.Bitmap(imageWidth, imageHeight);

            Graphics g = Graphics.FromImage(image);

            g.Clear(BackgroundColor);

            Random rand = new Random();

            //给背景添加随机生成的燥点
            if (this.Chaos)
            {

                Pen pen = new Pen(Colors[rand.Next(Colors.Length - 1)], 0);
                int c = Length * 5;

                for (int i = 0; i < c; i++)
                {
                    int x = rand.Next(image.Width);
                    int y = rand.Next(image.Height);

                    g.DrawRectangle(pen, x, y, 1, 1);
                }
            }

            int left = 0, top = 0, top1 = 1, top2 = 1;

            int n1 = (imageHeight - FontSize - Padding * 2);
            int n2 = n1 / 4;
            top1 = n2;
            top2 = n2 * 2;

            Font f;
            Brush b;

            int cindex, findex;

            //随机字体和颜色的验证码字符
            for (int i = 0; i < code.Length; i++)
            {
                cindex = rand.Next(Colors.Length - 1);
                findex = rand.Next(Fonts.Length - 1);

                f = new System.Drawing.Font(Fonts[findex], fSize, System.Drawing.FontStyle.Bold);
                b = new System.Drawing.SolidBrush(Colors[cindex]);

                if (i % 2 == 1) top = top2;
                else top = top1;

                left = i * fWidth;

                g.DrawString(code.Substring(i, 1), f, b, left, top);
            }

            //画一个边框 边框颜色为Color.Black
            //g.DrawRectangle(new Pen(Color.Black, 0), 0, 0, image.Width - 1, image.Height - 1);
            // g.Dispose();

            //产生波形
            // 图片路径 如果扭曲则选择为True 波形的幅度倍数，越大扭曲的程度越高，一般为3 波形的起始相位，取值区间[0-2*PI)
            if (IsTwist)
            {
                double ro1 = rand.Next(1, 4);
                double ro2 = rand.Next(1, 5);
                int ro3 = rand.Next(1, 100);
                bool bxDir = true;
                if (ro3 % 2 == 0) bxDir = false;
                image = TwistImage(image, bxDir, ro1, ro2);
            }
            return image;
        }
        #endregion

        #region 生成随机字符码
        /// <summary>
        /// 生成随机字符码
        /// </summary>
        /// <param name="codeLen">长度</param>
        /// <returns></returns>
        public string CreateVerifyCode(int codeLen)
        {
            if (codeLen == 0)
            {
                codeLen = Length;
            }

            string[] arr = CodeSerial.Split(',');

            string code = "";

            int randValue = -1;

            Random rand = new Random(unchecked((int)DateTime.Now.Ticks));

            for (int i = 0; i < codeLen; i++)
            {
                randValue = rand.Next(0, arr.Length - 1);

                code += arr[randValue];
            }

            return code;
        }

        /// <summary>
        /// 生成随机字符码
        /// </summary>
        /// <returns></returns>
        public string CreateVerifyCode()
        {
            return CreateVerifyCode(0);
        }
        #endregion

        //生成Gif动画验证码

        #region 生成干扰线
        private void DisposeImageBmp(ref Bitmap ImageFrame)
        {
            //创建绘图对象
            Graphics ImageGraphics = Graphics.FromImage(ImageFrame);
            //创建随机对象
            Random rand = new Random();
            int cindex = rand.Next(Colors.Length - 1);
            //创建铅笔对象
            Pen ImagePen = new Pen(Colors[cindex], 1f);

            //创建随机点
            Point[] RandPoint = new Point[2];
            //随机画线
            for (int i = 0; i < PointNum; i++)
            {
                RandPoint[0] = new Point(rand.Next(ImageFrame.Width), rand.Next(ImageFrame.Height));
                RandPoint[1] = new Point(rand.Next(ImageFrame.Width), rand.Next(ImageFrame.Height));
                ImageGraphics.DrawLine(ImagePen, RandPoint[0], RandPoint[1]);
            }
            ImageGraphics.Dispose();
        }
        #endregion

        #region 输出Gif动画
        /// <summary>
        /// 输出Gif动画
        /// </summary>
        /// <param name="code">字符串</param>
        /// <returns></returns>
        private void CreateImageGif(string code)
        {
            ADGifEncoder GifPic = new ADGifEncoder();
            MemoryStream BmpMemory = new MemoryStream();
            GifPic.Start();
            //确保视觉残留
            GifPic.SetDelay(5);
            //-1:no repeat,0:always repeat
            GifPic.SetRepeat(0);
            for (int i = 0; i < 10; i++)
            {
                //创建一帧的图像
                Bitmap ImageFrame = CreateImageBmp(code);
                //生成随机线条
               if(IsPoint) DisposeImageBmp(ref ImageFrame);
                //输出绘图,将图像保存到指定的流
                ImageFrame.Save(BmpMemory, System.Drawing.Imaging.ImageFormat.Png);
                ImageFrame.Dispose();
                ImageFrame = null;
                GifPic.AddFrame(Image.FromStream(BmpMemory));
                BmpMemory = new MemoryStream();
            }
            GifPic.OutPut(ref BmpMemory);
            HttpContext.Current.Response.ClearContent();
            //配置输出类型
            HttpContext.Current.Response.ContentType = "image/Gif";
            //输出内容
            HttpContext.Current.Response.BinaryWrite(BmpMemory.ToArray());
            BmpMemory.Close();
            BmpMemory.Dispose();
        }
        #endregion

        #region 输出Jpg图片
        /// <summary>
        /// 输出Jpg图片
        /// </summary>
        /// <param name="code">字符串</param>
        /// <returns></returns>
        private void CreateImageJpg(string code)
        {
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            Bitmap ImageFrame = CreateImageBmp(code);
            if (IsPoint) DisposeImageBmp(ref ImageFrame);
            ImageFrame.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);

            HttpContext.Current.Response.ClearContent();
            HttpContext.Current.Response.ContentType = "image/Jpeg";
            HttpContext.Current.Response.BinaryWrite(ms.GetBuffer());

            ms.Close();
            ms = null;
            ImageFrame.Dispose();
            ImageFrame = null;
        }
        #endregion

        #region 输出图片
        /// <summary>
        /// 输出图片
        /// </summary>
        /// <param name="code">字符串</param>
        /// <returns></returns>
        public void CreateImage(string code)
        {
            if (IsGif) CreateImageGif(code);
            else CreateImageJpg(code);
        }
        #endregion

    }
}

